These forests require a climate which has a growth period of 4-6 months, Woodland is relevant today not only for its monetary value (the worth ofand a cool but mild winter period of 3-4 months, when their leaves are timber and associated timber products), but also for less tangible reasonsshed. Fig 1 shows the distribution of the major terrestrial biomes with such as conservation, scientific, cultural and material grounds (services):respect to mean annual temperature and precipitation; the deciduous forest • Woodland areas often include areas which are unmanaged – this givesbiome is also well supplied with rainfall, which is well distributed throughout rise to variety and structure within the woodland which is importantthe year. for the purposes of conservation. • The ecology of woodlands is an important branch of biology. NotDeciduous woodlands are multi-layered (stratified), usually with distinctive only in terms of species and populations, but natural woodland can actshrub, field and moss layers and often with a lower tree layer as well. as a reference point, or control, for measuring human impacts on theBroadleaf trees of oak, ash, elm, beech and maple are dominant within the environment. Woodlands, for example, can hold clues as to longer termbiome and the number of different tree species per hectare varies between changes in the earth’s natural environment, especially pollution and5-20, depending on local environmental conditions. Such tree species may climatic change. On a global scale, woods and forests act to helpgrow up to 50m tall; deciduous trees react to lower winter temperatures by stabilise climates through their role in the carbon cyclelosing their leaves to conserve moisture. Fig 2 shows the area of woodlandin Great Britain by main tree species. • Natural woodland is a major element of wilderness and amenity and therefore has cultural significance. The tragedy, is that so little primaryFig 2. Main tree species in Great Britain deciduous forest remains.

deciduous Role of Succession

17 % Pine Natural woodland is a product of succession – that is a gradual and 31 % oak predictable change in plant and animal species over time. Following a clearance of the ground (this can be natural such as an ice age or fire, or human-centered, e.g. the abandonment of an arable field), pioneer ‘weed’ 33 % spruce communities will invade and then be replaced by grassland. If left un- grazed and managed for a few years, bushes will invade and the land will 9 % other mixed convert into scrub. Eventually tree species will be able to colonise and so broadleaves the area is changed into a woodland. 6 % larch 4% other/mixed conifers

Fig 3 shows a diagrammatic profile of plant succession within an abandoned The woodland ecosystem, productivity and nutrient cyclesfield. As succession occurs (e.g. from weeds to woodland) there is usually The term ‘ecosystem’ describes the structure, organisation andan increase in: interrelationships between a community of plants, animals and microbes• (i) the stratification (structural complexity) and biomass mass of living together with the processes of energy flow and nutrient cycling. Feeding plants); relationships or food webs are often used to demonstrate woodland• (ii) the numbers of species occupying the site; complexity,• (iii) the growth rate or productivity of the vegetation. Compared to some lower-latitude ecosystems and biomes, temperateFig 3. Plant succession deciduous forest has low productivity – Fig 4). Sere Fig 4. Comparison of ecosystem productivity early seral mid-seral late seral climax stage stage vegetation Ecosystem Productivity Mean biomass Pioneer kg/m2/Yr) (kg/m2) communities Tropical rain forest 2.2 45 Tropical deciduous forest 1.6 35 Tropical scrub 0.37 3 Savanna 0.9 4 Mediterranean sclerophyll 0.5 6 weeds grasses shrubs and deciduous Desert 0.003 0.002 scrub woodland Temperate grassland 0.6 1.6 (oak, ash) Temperate deciduous forest 1.2 32.5 5 years 25 years 150 years Boreal forest 0.8 20 Tundra and mountain 0.14 0.6 Open ocean 0.12 0.003 Time Continental shelf 0.36 0.001 Estuaries 1 1Succession is able to occur because species modify the site making it moresuitable for the next colonisers, i.e. pioneer communities are able to bindthe soil with their roots thus stabilising the environment; vegetation also ‘Productivity’ refers to the rate of energy captured and ‘biomass’ thealters the properties of the soil by adding organic matter through its weight of living material within the system (Fig 5).decomposition.This means that the ‘natural vegetation’ of much of SE Britain (its ‘climaticclimax’) is deciduous woodland, dominated by oak, ash and beech. Parts ofScotland and in NW Britain this pattern of tree is replaced by more hardyconiferous species, e.g. pines and deciduous birch or by smaller shrubbyplants which are better adapted to withstanding the climatic extremes ofcold.

Soils of temperate deciduous woodland Multi-Purpose Systems

The characteristic soils of the temperate deciduous forests are brown earths Woodland management is often complex, not least because of the range ofand similar ‘brown’ soils. There is a complex interrelationship between demands (or services) that a single area of woodland may be expected tosoil and vegetation, each factor having an influence on the other. Brown provide, both locally and globally. Hence the idea of managing a ‘multi-earths are generally well-drained, with a reddish-brown horizon which purpose’ system. Woodlands represent resources of great versatility –extends below about 30cm in depth. offering an enormous variety of ‘products’, i.e. • Commercial timber and fuelwoodThe soils occur mainly below altitudes of 300m and so dominate the warmer • Recreational space for leisure activitieslowlands of Britain (covering about 50% of the land surface in England and • Habitats for flowers, birds and insectsWales). Typically, they have a pH of around 5.5-6.5 • Shelter for stock, e.g. deerBrown earths are traditionally associated with broadleaf, deciduous forest • Hydrological significance, e.g. interceptionand many now lie below fertile improved grasslands since the removal ofthe original woodland cover. The upper layers of the soil are biologically In addition to the above, the woodland resource may also have to provideactive – this is denoted by a rich mixture of humus and mineral matter. The land for commoners, transport routes (major roads and pipelines) andlower ‘B’ horizon is seldom separated from the upper ‘A’ horizon because facilities for education and interpretation.of soil mixing by earthworms. Inevitably there are conflicts of interest between different uses and userIn areas where soils are freely draining, the profile may become increasingly groups. In particular there are often differing opinions regarding access forleached, with the loss of macro-nutrients such as iron and aluminium ions recreation, conservation and commercial timber production. Even withininto the lower horizons of the soil. (For details on profiles see GeoFactsheet particular user groups there may be disagreement, e.g. shooting and paintball;131 on Soils in Britain) off-road vehicles and orienteering. The recreation activity causing most concern in a number of larger woodland systems, like the New Forest, isHistorical Change riding in groups. Shod horses damage vegetation by widening paths underHuman activity in the last 3,000 years has cleared many areas of their natural damp conditions.tree vegetation. Now in many places, just the remnants or relic fragments ofpreviously extensive forests remain. Yet throughout history, trees have beenpart of our cultural landscape and have been managed and used. From the Case Study 1 – Hayley Wood, CambridgeshireBronze age onwards land was cleared for agriculture, both pastoral and For many centuries Hayley wood had been utilised by people and itsarable; burning was the main method of clearance. One example of an area history has been recorded for the last 700 years. The wood, now ownedextensively cleared in this way is Malham in North Yorkshire where there is by Cambridgeshire Wildlife Trust, has been the subject of much research.evidence of Iron Age field systems and boundaries. Agriculture in that area Occupying a 150 ha site, the area is dominated by species of oak, ash,today is dominated by sheep farming on rough grassland. The ‘natural’ elm, maple and willow. Hayley Wood’s significance in historical timesvegetation in this area is deciduous woodland, but grazing prevents was as a source of timber for construction, and the smaller ‘underwood’regeneration of saplings. Where the natural process of succession has been used for firewood and other purposes. Much of the hazel and willowarrested in this way, we are left with a ‘plagio-climax’. was coppiced on 10-15 year cycles within selected areas or ‘coupes’ harvested at intervals of approximately seven years to provide timberNatural fires may also have been responsible for a significant amount of for the manufacture of wooden sticks for fences etc.woodland clearance. Lightning, quite capable of starting a fire, caused significantareas to be cleared. Early settlers would have taken advantage of the cleared Fig 7ground and used it for grazing animals. Similarly many areas within thetemperate grasslands of the prairies could support deciduous woodland.Woodland facts and figures Coppice stool aboveToday in the UK about 12% of the land area is wooded (this includes both groundconiferous and deciduous species). This figure compares favourably to acentury ago when only 4% of the UK was afforested yet the figure issignificantly lower than EU average of around 45% (but remember thatthere are considerable differences in population densities between memberstates).Fig 6 Areas of woodland in thousands of hectares (2003) – sourceNational Statistics Underwood trees such as beech and hazel are cut near to Conifers Broadleaves Total woodland ground level and them regrow from the remaining stump or (non-deciduous) (deciduous) area 'stool'. This is a sutainable method of generating timber. England 372 739 1,111 Wales 163 123 286 Scotland 1052 275 1327 Other trees such as oaks were allowed to reach maturity before harvest; Great Britain 1,587 1,137 2,724 these ‘standards’ were felled and used in construction of buildings etc. During the 19 century the importance of Hayley Wood as a supplier ofUntil the 1980’s the area under broadleaf (deciduous) woodland continued timber products decreased. Coal became increasingly important andto fall and losses of ancient semi-natural woodland (woodland dating back metal substitutes became available as alternatives to timber products.to before 1600) were particularly severe. At this time nature conservation The wood then became valued as a cover for game, fox hunting andpolicies became more widespread in both public and private woodlands. shooting. The wood is now managed for both people and wildlife.Since this time the Forestry Commission has been working with landownersand conservation groups to improve not only the area under woodlandcover, but also the quality of the resource (both commercially andaesthetically) with an emphasis on planting deciduous woodlands of thenew forests of Mercia.

Case Study 2 Bialowieza Forest, Poland

Fig 8. Bialowieza Forest 254 lichen species, 80 liverworts and more than 3,000 fungi have been recorded in addition to the 10 or so dominant species of trees. Narewka There are 54 species of mammal including European bison, grey wolf, lynx, otter and beaver. An estimated 230 species of birds are found within the reserve including capercaillie, black stork, crane, and a large BIALOWIESKI number of raptors such as spotted eagle and booted eagle. Approximately Najowka NATONAL 8,500 species of insects have been recorded. PARK There are about 95,000 visitors annually, 30% of which visit the strict Bialowieza preservation area where access is limited to guided groups. Trained guides are provided by the tourist offices and are assigned to individual tourist groups and youth excursions, in accordance with park management. Guided trips use traditional horse drawn vehicles to get round the park. This vast area of forest - 57,000 ha (1,250 sq. km), is located in North east-central Poland on the border with Belarus. Situated on the The park area consists of a strict core zone (4,747ha) and a protective hydrological divide between the Baltic and Black Seas, it lies in the drainage zone (276ha) around the village. Here activities such as clear felling, basin of the River Narewka, a tributary of the Narew. The region experiences hunting and the use of insecticides are banned. Access is limited to research a temperate continental cool climate, where mean annual precipitation is and guided visitors, all motor vehicles are banned. The ‘Hwozna’ 650 mm and mean annual temperature is 6.8° C. Protective District covers an area of 5,155ha. It comprises of a mosaic of old growth forest stands, including species that are not represented in Part of the area was designated a UNESCO Biosphere reserve in 1993 other areas of the park. This is surrounded by a 1km wide forest buffer because of its ecological diversity and cultural significance - a total of 184 zone to the north-west and south. burial sites from the 11th and 12th centuries have been found in the region. Within the preservation area of the forest there are 632 species of plants, constituting about 29% of the flora of Poland.

Contemporary Problems and The future of Deciduous woodlands Fig 10. Woodland under threat from airportsAfter reaching a low point early in the 20th century, the area of woodlandsand forests in Britain has risen steadily since. Trees and woodlands also airport area under area subject Total:have a higher political currency than they once did. This is due in part to threat: to wider haclimate change and Local Agenda 21 whereby woodlands are recognised as ha (acres) threat: ha (acres)important pollution ‘sinks’. Visits to forests (both deciduous and coniferous) (acres)are also more commonplace than 20 years ago with an increased range of Birmingham 22.4 (55.33) 0recreation facilities and activities being provided by organisations such asthe National Trust, Woodland Trust, Royal Forestry Society and the East Midlands 4.05 (10) 0Forestry Commission. There have also been notable successes in terms ofurban forests, the National Forest and Millennium Forest initiatives. New Rugby/Coventry 34.12 (84.28) >400 (988)However there are always pressures and issues within areas where there isa rich mosaic of land-uses. The box below some of the threats to woodlands Coventry 9.55 (23.59) 0which can operate at a range of scales. Total 70.12 (173.2) >400(988) 470.12Fig 9. Woodland threats (1161.2)

impact of climatic air pollution (including

Direct Impacts tourism change acid rain and gaseous • Loss of good quality habitats (not only woodlands but associated pollutants hedgerows etc) • Noise – disturbance of wildlife, particularly nesting birds land-take (urban • Smell and visual intrusion of airports has a negative impact on forest development, airport amenity value expansion and wooland threats • Pollution from aircraft, in particular oxides of nitrogen. This has agricultural impacts at a range of scales intensification) • Development of improved infrastructure and terminal buildings will result in land-take and increased loss of forest. introduction of alien Indirect Impacts deforestation water / groundwater invasive species (eg • More people would be attracted to living close to the airport. This (sometimes illegal) pollution pests and diseases) puts pressure on the woodland resources within the catchment of any new proposal / expansion as there will be a need for new housingOne woodland threat which is of particular concern is the projected expansion • There will likely be a substantial increase in visitors to local woodlandand development of airports. Fig 10 shows areas of woodlands under threat amenities; sensitive areas of ancient forest can be damaged (in particularfrom airport expansion in the Midlands. There are number of direct and litter, loose dogs, stealing dead-wood, setting fire to hollow trees etc)indirect impacts. 4170. Temperate Deciduous Forest Biomes Geo Factsheet www.curriculum-press.co.uk

Review Questions Data Response Questions

1. Compare the nutrient cycle of a tropical rain forest to that of a deciduous The diagram below shows a food web in a temperate deciduous forest. forest. Explain why there are such differences. Producers Consumers

Tropical rain forest Spider

Dead Springtails Ground

Weasel2. Describe and explain the key features of soils associated with remains and beetles temperature deciduous forests. decomposed Woodlice Shrew material Earthworms Mole3. Outline a fieldwork programme you could undertake in order to examine the productivity of two different deciduous woodlands. The diagram below shows a trophic level diagramGuidelines for answers1. Tropical Rain forest – biomass store much larger compared to litter TL4 Tertiary consumers and soil, whereas in the deciduous forest the stores tend to be much TL3 Secondary consumers more evenly balanced. This means in the tropical forest much of the TL2 Primary consumers nutrient store is locked up in tree biomass – this is why deforestation has such a serious impact on the forest productivity. In both systems there are similar transfers in terms of decomposition and loss by leaching. TL1 producers However some inputs and outputs are significantly different, e.g. nutrient dissolved in rainfall, and input from weathered rock. This can be explained through a discussion of climatic differences, and how this in turn impacts on rates of weathering for example. (a) (i) Define a food web [1]

2. Just as in the text you should perhaps consider the distribution of soils (ii) Explain what is meant by a trophic level [2] and link soil type to process. The development of particular horizons within the soil is as a result of particular processes which occur within (iii) For each of the four trophic levels shown above name one example certain layers of the soil. The soil colour is also partly a function of shown on the food web [4] these processes as well as the impact of geology and vegetation. Note – Factsheet 131 provides a more detailed account of brown earth (iv) Explain the function of decomposers [2] development (v) Suggest why less energy is available at each successive trophic3. Productivity can be approximated by estimating tree volume and relating level [2] this figure to tree age. Start by selecting two appropriate woodlands where the ages of trees can be deduced. Decide on a suitable sampling (vi) Outline the impact on the woodland ecosystem of a very harsh strategy or frame, i.e. stratified, systematic or random. Collect data on Spring which decimated blue tit numbers [4] tree height by using a clinometer and then trigonometry to estimate in metres. Then measure the girth of the tree and convert this circumference figure into a cross-sectional area. Repeat the measurement for 20 or so trees in each woodland. Use the cross-sectional area value and height to estimate the volume of a cylinder. Compare the results for both woodlands. For further fieldwork projects see “Fieldwork Investigations for Geography”

Further Reading O’Hare, G (1989) Soils, Vegetation and Ecosystems (Oliver and Boyd). Now out-of-print, but you can probably find a copy in a cupboard at school/college! Rackham, O (2001) Trees and Woodland within the British Landscape (Weidenfeld & Nicholson history) www.magic.gov.uk MAGIC - Multi-Agency Geographic Information for the Countryside. A one-stop shop for rural and countryside information. Here you can get information on woodland cover and grant schemes, which can then be viewed as a scalable map.

Acknowledgements; This Factsheet was researched and written by David Holmes who lectures at King Edward VI College Stourbridge. Curriculum Press, BankHouse, 105 King Street, Wellington, Shropshire, TF1 1NU. Geopress Factsheets may be copied free of charge by teaching staff or students, provided that theirschool is a registered subscriber.No part of these Factsheets may be reproduced, stored in a retrieval system, or transmitted, in any other form or by any other means, without the prior permission ofthe publisher. ISSN 1351-5136